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JSON Diff Viewer

Paste two JSON objects to instantly see what changed — added lines in green, removed in red. Auto-formats JSON for clean comparison. Perfect for debugging API responses and config changes. Runs entirely in your browser.

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Examples:
+3 added−2 removed3 unchanged
{
"name": "Alice",
− "age": 30,
− "role": "admin"
+ "age": 31,
+ "role": "user",
+ "email": "[email protected]"
}
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Frequently Asked Questions

How do I compare two JSON objects?▼

Paste the first JSON into the left panel and the second into the right panel. The tool instantly highlights added lines in green, removed lines in red, and unchanged lines in gray — giving you a clear visual diff.

Does JSON Diff Viewer auto-format messy JSON?▼

Yes. Both panels automatically pretty-print your JSON before comparing, so even minified or inconsistently indented JSON is reformatted for a clean, readable diff. You don't need to format it yourself.

Is my JSON data sent to any server?▼

No. This tool runs entirely in your browser using JavaScript. Your JSON never leaves your machine, making it safe to use with API responses, configuration files, or any sensitive data.

Can I use this to compare API responses?▼

Absolutely. Paste two API responses side-by-side to see exactly what fields changed between requests or deployments. It's especially useful for debugging REST API contracts during development or testing.

What is the difference between JSON diff and JSON merge?▼

JSON diff shows the differences between two JSON documents — what was added, removed, or changed. JSON merge combines two objects, with one overwriting the other's conflicting keys. This tool focuses on diffing, not merging.

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